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String.IsNullOrWhiteSpace in LINQ Expression

...INQ provider to deliver an optimized query. During this transformation not all C# statements are supported, as it either is not possible to translate them to a back-end specific query (e.g. SQL) or because the implementer did not foresee the need for the statement. In contrast IEnumerable<T>...
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How to format a java.sql Timestamp for displaying?

...SQL and want the database itself to perform the conversion, use this: DATE_FORMAT(date,format) If you prefer to format using Java, use this: java.text.SimpleDateFormat SimpleDateFormat dateFormat = new SimpleDateFormat("M/dd/yyyy"); dateFormat.format( new Date() ); ...
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How do I set bold and italic on UILabel of iPhone/iPad?

...t { return with([.traitBold, .traitItalic]) } func with(_ traits: UIFontDescriptor.SymbolicTraits...) -> UIFont { guard let descriptor = self.fontDescriptor.withSymbolicTraits(UIFontDescriptor.SymbolicTraits(traits).union(self.fontDescriptor.symbolicTraits)) else { ...
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How to show google.com in an iframe?

... The reason for this is, that Google is sending an "X-Frame-Options: SAMEORIGIN" response header. This option prevents the browser from displaying iFrames that are not hosted on the same domain as the parent page. See: Mozilla Developer Network - The X-Frame-Options response ...
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Why doesn't 'ref' and 'out' support polymorphism?

...nswer as the basis for this blog entry: Why do ref and out parameters not allow type variation? See the blog page for more commentary on this issue. Thanks for the great question. ============= Let's suppose you have classes Animal, Mammal, Reptile, Giraffe, Turtle and Tiger, with the obvious s...
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How do I execute a command and get the output of the command within C++ using POSIX?

...use the C stdio API, I prefer the iostreams API. popen requires you to manually clean up the FILE handle, pstreams do that automatically. popen only accepts a const char* for the argument, which requires care to avoid shell injection attacks, pstreams allows you to pass a vector of strings similar t...
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What's the function like sum() but for multiplication? product()?

...Older info: Python 3.7 and prior The function you're looking for would be called prod() or product() but Python doesn't have that function. So, you need to write your own (which is easy). Pronouncement on prod() Yes, that's right. Guido rejected the idea for a built-in prod() function because he t...
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NodeJS / Express: what is “app.use”?

...gt;) for every middleware layer that you want to add (it can be generic to all paths, or triggered only on specific path(s) your server handles), and it will add onto your Express middleware stack. Middleware layers can be added one by one in multiple invocations of use, or even all at once in seri...
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Centering a background image, using CSS

...nd-image:url(https://upload.wikimedia.org/wikipedia/commons/thumb/8/8b/Dore_woodcut_Divine_Comedy_01.jpg/481px-Dore_woodcut_Divine_Comedy_01.jpg); background-repeat:no-repeat; background-position: center; background-size: cover; html{ height:100% } body{ background-image:url(https://uplo...
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Find index of last occurrence of a substring in a string

...variable name that people should avoid in python is abc; there's a module called abc in the native API. – progyammer May 28 '19 at 10:31 add a comment  |  ...